The Station
ALAMO is two machines that only make sense together: one in a paddock in Palo Pinto County, one in a data centre in Dallas. The radio, the antenna switch, the relays and these pages all hang off that pair.
ALAMOPI
A Raspberry Pi in the shack. It is the gateway for the site network, throws the relays that power the radio and key it, watches the Flex and reports its state, and relays antenna-switch commands. It dials out to the exit node and keeps that link open — nothing on the internet can reach it directly.
ALAMO-EXIT-NODE
A small virtual machine with a fixed public address that never changes. It holds the far end of the tunnel, serves the pages you are reading now, and forwards traffic back down to Graford. It is how anything reaches ALAMO at all.
Everything else described on this page sits behind one or the other of those two.
The radio
The transceiver is a FlexRadio 6700, running firmware 4.2.20. It is a software-defined radio, which in practice means it does not especially care where its operator is standing. It puts itself on the network and is reached through FlexRadio’s SmartLink service, so the operating position at Fort Worth sees it much as it would see a radio on the desk.
That is the entire reason the station is possible. A conventional transceiver can be made to work remotely, but it becomes a project about adapters and audio interfaces. The Flex was designed for this from the start.
The antenna switch
In front of the radio is a 4O3A Antenna Genius 8×2 Plus, firmware 4.1.16, wired to the Flex’s second antenna port. Eight antenna positions, two radio ports. The Flex holds radio port one; port two is unused and stays that way until there is a second radio to put on it.
| Port | Antenna | Notes |
|---|---|---|
| 1 | Longwire | The antenna the site exists for — the run a suburban lot cannot give you. |
| 2 | Fan dipole | Cut for 20, 15 and 10 metres. |
| 3 – 7 | Unused | Spare positions, greyed out in the control page until something is connected. |
| 8 | Disconnected | Deliberately marked as a hazard. Selecting it puts the radio into an open port. |
The switch is controlled from the antenna page Login, which refuses to move the switch while the radio reports that it is transmitting. Hot-switching an antenna relay is how you turn a working switch into a paperweight.
The relays
A four-channel relay board is wired to the Pi’s GPIO. Two channels are in service and two are spare. Note that nothing here switches mains — the site has full mains power and the radio stays plugged in. These are control lines.
| Relay | Function | Notes |
|---|---|---|
| 1 | Remote on | Closes the Flex’s REMOTE ON input — the rear-panel RCA jack that brings the radio out of standby. It is a signal line, not a power feed: the radio stays connected to the mains, and this is what wakes it. |
| 2 | PTT | Keys the transmitter. Drops itself automatically after fifteen seconds, so a stuck request cannot hold the radio in transmit. |
| 3 | Spare | Wired and available, nothing on it. |
| 4 | Spare | As above. |
Relay state does not travel straight from the browser to the Pi. The control page Login writes a requested state to the exit node, and the Pi polls for it and acts. That indirection is on purpose: the site never accepts an inbound connection, and if the tunnel drops the page notices, because the Pi stops confirming that it is alive.
How a click reaches the paddock
Three different jobs, three different paths, and it is worth being clear about which is which.
- Relays — the browser writes a request on the exit node; the Pi polls it, operates the GPIO, and reports back. Deliberately indirect.
- Rig status — a monitor on the Pi watches the Flex and pushes what it sees up to the exit node, which streams it live to the status page. One way only; the page cannot talk back.
- Antenna switch — the web server opens a connection through the tunnel to a small relay running on the Pi, which passes it to the switch. The switch only grants full access to clients on its own LAN, and going via the Pi is what makes the web server look like one.
The site network
The site has full mains power, so there is no solar budget to manage and no battery to nurse — the equipment simply stays on.
Graford runs its own private LAN, with the Pi as its gateway. The radio and the antenna switch live on it and nowhere else. The Pi’s other side faces whatever internet the site has, and its third interface is the WireGuard tunnel to Dallas.
From the exit node’s point of view the entire Graford network is simply reachable down the tunnel, at about twenty-four milliseconds. From the internet’s point of view it does not exist.
What is public and what is not
The story page and the rig status page are open to anyone. Anything that can change the state of hardware — relays, antenna selection, site audio — sits behind a login. There is no version of this station where a stranger gets to key the transmitter.
If you do not have a login and want to see what those pages actually look like, there are screenshots of all three — static captures, not live data.
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